The present invention relates to a gas burner for a boiler and for industrial applications, of the type comprising:                a support wall connectable to a combustion chamber of the boiler or industrial application, the support wall having an inlet opening for introducing a mixture of fuel gas and oxidant into the burner,        a tubular diffuser wall having a first end connected to the support wall in flow communication with the inlet opening, a second end closed by a closing bottom, and a perforation for the passage of the mixture of gas from the inside of the burner to an outer side of the diffuser wall, where the combustion occurs,        a tubular element positioned inside the diffuser wall and having a base connected to the support wall in flow communication with the inlet opening and a free end forming an outlet opening in an intermediate position between the first end and the second end of the diffuser wall.        
This known burner is described in patent application WO2009/112909 by the Applicant and aims at overcoming problems of noise of the previously known cylindrical burners. By virtue of the tubular element in the burner, the resonance frequency of the burner can be modified and the vibration frequencies induced during the operation can be moved away from the resonance frequencies of the burners, thus reducing the noise thereof and the cyclical mechanical stress caused by the vibrations themselves.
However, the burners provided with the “noise-reducing” tubular element display a non-uniform flame distribution on the outer surface of the diffuser, thus preventing optimal exploitation of the size of the burner for heat generation purposes.
Finally, the local heating of the diffuser wall caused by the presence of the “noise-reducing” tubular element causes a high risk of flashback of the fuel-oxidant mixture still upstream of the diffuser wall.
It is the object of the present invention to provide a gas burner of the above-described type, but modified so as to overcome the observed drawbacks of the prior art.